Importance of expert impartiality

“Where the core issue in a case turns, as it does here, on the court’s ability to evaluate the competing and finely balanced medical judgments of rival experts, the court’s confidence in the independence and impartiality of the respective experts must play an important role.”

In Exp v Dr Charles Simon Baker [2015] EWHC 1289 (QB), the trial judge was called upon to assess the expert evidence regarding interpretation of MR imaging regarding an aneurysm. The comment above (at [73]) was made because neither the defendant nor the defendant’s retained experts, in their CVs provided to the court, disclosed their ‘lengthy and extensive’ professional connection: [52]. This was despite an interlocutory direction (which may well have been a standard direction) requiring experts at the time of producing their reports, to incorporate details of any employment or activity which raised a possible conflict of interest.

The expert had in fact trained the defendant during his 7 years of specialist radiology training and in particular had trained him for more than 2 years as a registrar and senior registrar in neuroradiology and interventional radiology.They had written a paper together (not shown on the expert’s CV) and there were other connections such that the trial judge said that the defendant’s expert had played a relatively prominent part as a mentor of the defendant:[54]. It emerged that the defendant had suggested the retainer of the particular expert: [53].

The trial judge said that the defendant knew the details of the relationship and it was ‘fair and economical‘ that he should disclose them, rather than have the other party be ‘expected to engage in time consuming detective work‘: [51].

An aspect of the expert’s evidence was also criticised, in that he had referred to a published study without making reference to later published criticisms of it: [60] – [61].

The trial judge concluded at [55] that there was a very substantial failure on the part of the expert and the defendant to disclose, with adequate particularity, the nature and extent of the expert’s connection with the defendant, so that the Court would have a complete understanding of all matters that could realistically affect the independence of the expert witness.